Two-part cutters for bucket and wheel excavators, which are formed with teeth which cut into the ground, can have a tooth which can be removably affixed in a holder, the latter being mounted in turn, e.g. by welding, to the support which can be a bucket or scoop.
The connecting means may include a claw coupling in which, for example, a pair of claw like arms spaced apart on the holder to form a bifurcation, straddle a web or shank of the tooth. These two arms or cheeks may be referred to hereinafter as the coupling claws of the holder.
The cutting tooth can be provided with the aforementioned web or shank receivable between the coupling claws of the holder and thereby forming a counter claw, as well as a pair of cover claws lying above and below the coupling claws of the holder and bridged by this web.
The counter claw, web or shank can be locked in place within the holder by a fastener.
When the cutter holder is welded or otherwise connected to the bucket or other support of a bucket or wheel excavator, the tooth may be replaced upon removal of the fastener and thus may constitute a wearable element which can be exchanged quickly and simply.
In the past, the fastener has generally been a pin and the counter claw or web was coterminous with the cover claws of the cutter. In place of a pin, a rolled compression sleeve could also be used, the pin or sleeve being inserted through aligned bores traversing the coupling claws of the holder, i.e. the cheeks thereof, as well as the counter claw or web.
Since the tooth undergoes considerable abrasive wear, especially along the lateral flanks which were provided with the pin or sleeve, deformation could occur which made it difficult to replace the tooth or allow the tooth to loosen by itself.
Tooth-replacement problems were especially the case in excavators in which the number of teeth and hence tooth holders was comparatively large and thus the tooth holders had to be fastened with a minimum distance from one another. This complicated removal, especially where the pins were inserted in the direction in which the row of teeth extended. In this case it was particularly difficult to mount or remove a tooth or even obtain access to the pin.